Buggy code:
, new String [ ] { "E" , "x<seq2seq4repair_space>a<seq2seq4repair_space>b<seq2seq4repair_space>c<seq2seq4repair_space>d" , "5" , "2f" , "h" , "B-8" , "peach" , String . valueOf ( Long . MIN_VALUE ) , String . valueOf ( Double . MAX_VALUE ) , String . valueOf ( Short . MAX_VALUE ) , String . valueOf ( Byte . MAX_VALUE ) , "F" } , new String [ ] { "F" , "y<seq2seq4repair_space>a<seq2seq4repair_space>b<seq2seq4repair_space>c<seq2seq4repair_space>d" , "2" , "3.14159f" , "g" , "B-1" , "HÅT" , "-44" , "343.034435444" , "-3" , "0" , "E" } , new String [ ] { "G" , "x<seq2seq4repair_space>a<seq2seq4repair_space>b<seq2seq4repair_space>c<seq2seq4repair_space>d" , "3" , "-1.0" , "f" , "C-100" , "sin" , "323254543543" , "4.043544" , "5" , "100" , "D" } , new String [ ] { "H" , "y<seq2seq4repair_space>a<seq2seq4repair_space>b<seq2seq4repair_space>c<seq2seq4repair_space>d" , "0" , "1.4E-45" , "e" , "C-88" , "HØT" , "1023423423005" , "4.043545" , "10" , "-50" , "C" } , new String [ ] { "I" , "x<seq2seq4repair_space>a<seq2seq4repair_space>b<seq2seq4repair_space>c<seq2seq4repair_space>d<seq2seq4repair_space>e<seq2seq4repair_space>f" , "-2147483648" , "1.0e+0" , "d" , "A-10" , "sín" , "332422459999" , "4.043546" , "-340" , "51" , "B" } , new String [ ] { "J" , "y<seq2seq4repair_space>a<seq2seq4repair_space>b<seq2seq4repair_space>c<seq2seq4repair_space>d<seq2seq4repair_space>e<seq2seq4repair_space>f" , "4" , ".5" , "b" , "C-7" , "HOT" , "34334543543" , "4.0000220343" , "300" , "2" , "A" } , new String [ ] { "W" , "g" , "1" , null , null , null , null , null , null , null , null , null } , new String [ ] { "X" , "g" , "1" , "0.1" , null , null , null , null , null , null , null , null } , new String [ ] { "Y" , "g" , "1" , "0.2" , null , null , null , null , null , null , null , null } , new String [ ] { "Z" , "f<seq2seq4repair_space>g" , null , null , null , null , null , null , null , null , null , null } } ; private Searcher getIndex ( boolean even , boolean odd ) throws IOException { } private Searcher getFullIndex ( ) throws IOException { } private IndexSearcher getFullStrings ( ) throws IOException , CorruptIndexException , LockObtainFailedException { } public String getRandomNumberString ( int num , int low , int high ) { } public String getRandomCharString ( int num ) { } public String getRandomCharString ( int num , int start , int end ) { } Random r ; public int getRandomNumber ( final int low , final int high ) { } private Searcher getXIndex ( ) throws IOException { } private Searcher getYIndex ( ) throws IOException { } private Searcher getEmptyIndex ( ) throws IOException { } @ Override public void setUp ( ) throws Exception { } public void testBuiltInSorts ( ) throws Exception { } public void testTypedSort ( ) throws Exception { } public void testStringSort ( ) throws IOException , ParseException { } public void testCustomFieldParserSort ( ) throws Exception { } public void testEmptyIndex ( ) throws Exception { } static class MyFieldComparator extends FieldComparator { int [ ] docValues ; int [ ] slotValues ; int bottomValue ; MyFieldComparator ( int numHits ) { } @ Override public void copy ( int slot , int doc ) { } @ Override public int compare ( int slot1 , int slot2 ) { } @ Override public int compareBottom ( int doc ) { } @ Override public void setBottom ( int bottom ) { } @ Override public void setNextReader ( IndexReader reader , int docBase ) throws IOException { } @ Override public Comparable value ( int slot ) { } } static class MyFieldComparatorSource extends FieldComparatorSource { @ Override public FieldComparator newComparator ( String fieldname , int numHits , int sortPos , boolean reversed ) { } } public void testNewCustomFieldParserSort ( ) throws Exception { } public void testReverseSort ( ) throws Exception { } public void testEmptyFieldSort ( ) throws Exception { } public void testSortCombos ( ) throws Exception { } public void testLocaleSort ( ) throws Exception { } public void testInternationalSort ( ) throws Exception { } public void testInternationalMultiSearcherSort ( ) throws Exception { } public void testMultiSort ( ) throws Exception { } public void testParallelMultiSort ( ) throws Exception { } public void testNormalizedScores ( ) throws Exception { } public void testTopDocsScores ( ) throws Exception { } public void testSortWithoutFillFields ( ) throws Exception { } public void testSortWithoutScoreTracking ( ) throws Exception { } public void testSortWithScoreNoMaxScoreTracking ( ) throws Exception { } public void testSortWithScoreAndMaxScoreTracking ( ) throws Exception { } public void testOutOfOrderDocsScoringSort ( ) throws Exception { } public void testSortWithScoreAndMaxScoreTrackingNoResults ( ) throws Exception { } private void runMultiSorts ( Searcher multi , boolean isFull ) throws Exception { } private void assertMatches ( Searcher searcher , Query query , Sort sort , String expectedResult ) throws IOException { <START_BUG> TopDocs hits = searcher . search ( query , null , expectedResult . length ( ) , sort ) ; <END_BUG> ScoreDoc [ ] result = hits . scoreDocs ; assertEquals ( hits . totalHits , expectedResult . length ( ) ) ; StringBuilder buff = new StringBuilder ( 10 ) ; int n = result . length ; for ( int i = 0 ; i < n ; ++ i ) { Document doc = searcher . doc ( result [ i ] . doc ) ; String [ ] v = doc . getValues ( "tracer" ) ; for ( int j = 0 ; j < ( v . length ) ; ++ j ) { buff . append ( v [ j ] ) ; } } assertEquals ( expectedResult , buff . toString ( ) ) ; } private HashMap getScores ( ScoreDoc [ ] hits , Searcher searcher ) throws IOException { } private void assertSameValues ( HashMap m1 , HashMap m2 ) { } }

Fix:
TopDocs hits = searcher . search ( query , null , Math . max ( 1 , expectedResult . length ( ) ) , sort ) ;